Electrically operated seat belt retractor

ABSTRACT

An emergency-locking seatbelt retractor having a solenoidoperated, spring-biased lock connected to the vehicle&#39;&#39;s electrical system to automatically unlock the retractor when the ignition circuit is energized, and to automatically lock the retractor in response to various abnormal vehicle operating conditions.

United States Patent Inventor William L. Pringle Grosse Pointe, Mich.

Appl. No. 797,429

Filed Feb. 7, 1969 Patented Oct. 5, 1971 Assignee Jim Robbins Seat BeltCompany Mount Clemens, Mich.

ELECTRICALLY OPERATED SEAT BELT RETRACTOR 7 Claims, 12 Drawing Figs.

US. Cl 180/82, 280/150 SB, 297/388 Int. Cl Br 21/10 Field of Search 280/SB; /82; 297/385, 380; 242/107 SB [56] References Cited UNITED STATESPATENTS 2,705,529 4/1955 Bullet a1 297/386 X 2,883,123 4/1959 Finnigan.280/150 X 3,240,510 3/1966 Spouge 180/82 3,294,339 12/1966 Fontaine297/388 X 3,308,902 3/1967 Carter 180/82 3,486,792 12/1969 Stoffel280/150 Primary Examiner-Kenneth H. Betts AtlorneysMarvin Bressler andJonathan Plaut ABSTRACT: An emergency-locking seatbelt retractor havinga solenoid-operated, spring-biased lock connected to the vehicle'selectrical system to automatically unlock the retractor when theignition circuit is energized, and to automatically lock the retractorin response to various abnormal vehicle operating conditions.

PATENTEDUBHSBH 3.610.361

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INVENTOR WILLIAM L. PRINGLE PATENTED 001 1 5 |97| SHEET 8 0F 4 INVENTORI WILLIAM L. PRINGLE ELECTRICALLY OPERATED SEAT BELT RETRACTORBACKGROUND OF THE INVENTION This invention relates to safety seatbeltsystems, and more particularly to a retractor system having electricalmeans for automatically unlocking a seatbelt retractor to allow the beltto be freely extended by the occupant during normal vehicle operatingconditions, but which automatically locks the retractor to prevent beltextension in response to certain abnormal vehicle conditions.

Emergency locking vehicle seatbelt systems of the prior art allow anoccupant of the belt to perform normal body motions within the vehiclein a relatively unrestrained manner because the seatbelt can be freelyextended and retracted to accommodate his motions. A retractor lockingmechanism, or some other means operable to prevent belt extension, isprovided for automatically preventing belt extension in response to anabnonnal vehicular condition, such as a sudden acceleration, ordeceleration, or an abnormal vehicle orientation. These conditions arenormally associated with an accident in which it is desirable torestrain the vehicles occupant against a sudden change in positionwithin the passenger compartment of the vehicle.

Usually prior art automatic locking mechanisms employ some form ofmechanical device for automatically locking or unlocking the retractorin response to a predetennined change in motion of either the vehicle orof the belt. A few automatic locking retractors of the prior art employan electrical actuator such as a solenoid for locking or unlocking theretractor but not in response to an emergency situation. The problem isthat it is necessary for the locking mechanism to be locked in responseto an abnormal condition. This abnormal condition could occursimultaneously with a failure of the vehicles electrical system whichwould deenergize the solenoid.

Two systems utilizing solenoids have been disclosed in U.S. Pat. No.3,308,902 to A. G. Carter, and in Pat. No. 3,294,339 to J. G. Fontaine.In each system, the retractor is normally locked to prevent beltextension. In the Carter patent, the solenoid unlocks the retractor whenthe ignition circuit is energized to allow the user to adjust the lengthof the belt. The solenoid then locks the retractor in response tocoupling of the belt buckle components. In the Fontaine patent, thesolenoid provides means for deliberately unlocking the retractor for apredetermined time interval to allow the user to either adjust thelength of the belt about his body, or to perform a few unrestrainedmovements.

SUMMARY OF THE INVENTION The broad purpose of the present invention isto provide an emergency-locking seatbelt retractor having anelectrically actuated lock that is automatically unlocked as thevehicles ignition circuit is energized, and automatically locked inresponse to certain predetermined vehicular conditions. Two embodimentsof the invention are disclosed. One is in the form of a rotary retractorthat is suited for mounting on the vehicles floor. The other is in theform of a novel linear retractor that is adapted for mounting in otherportions of the vehicle, as in the seat back where only a relativelyfiat storage space is available.

Either embodiment can be operated by the preferred electrical circuitwhich includes a solenoid and a movable retractor locking member. Thelocking member is spring biased toward its locking position. Thesolenoid is connected to the locking member such that, upon beingelectrically energized, it moves the locking member toward its releaseposition. The solenoid is energized concurrently with energization ofthe vehicle's electrical circuit to allow the user to connect the beltabout his body and perform body motions in a relatively unrestrainedmanner while the vehicle is being operated.

The circuit includes various sensing devices for detecting an abnormalvehicle condition to automatically deenergize the solenoid. When thesolenoid is deenergized, the locking member snaps into its lockingposition to prevent belt extension. When the vehicle resumes its nonnalmotion or orientation, the solenoid is again automatically energizedafter a predetermined time period to unlock the retractor.

Devices for deenergizing the solenoid include a'mercury switch which isresponsive to either a sudden change in vehicle momentum as an abruptacceleration or deceleration, or an abnormal vehicle orientation as whenthe vehicle is being tipped over or is climbing up a steep incline.Another device for deenergizing the solenoid comprises a connectionbetween the solenoids circuit and the vehicles braking system. Theconnection includes a switch that is automatically opened in response toa predetermined hydraulic pressure associated with the vehicle beingsuddenly braked.

Still further objects and advantages of the present invention willbecome readily apparent to those skilled in the art to which theinvention pertains upon reference to the following detailed description.

DESCRIPTION OF THE DRAWINGS The description refers to the accompanyingdrawings in which like reference characters refer to like partsthroughout the several views and in which:

FIG. lis a view of a vehicle incorporating a preferred emergency-lockinglinear retractor mounted in the overhead portion of the vehicle-spassenger compartment;

FIG. 2 is a perspective view of the preferred retractor upside down withrespect to its normal mounting position on the vehicles ceiling, andwith a portion of the housing removed to show its internal components;

FIG. 2A is a view showing the manner in which the belt is anchored tothe retractor;

FIG. 3 is an exploded view of the retractors carriage and lockingcomponents;

FIG. 4 is a view showing the locking member in its unlocked and lockedposition in solid and dotted lines respectively;

FIG. 5 is a view of the locking member in its release position;

FIG. 6 is a schematic view of the preferred electrical circuit;

FIG. 7 is a perspective view of the invention embodied in a rotaryretractor;

FIG. 8. is an exploded view of the rotary retractor of FIG. 7;

FIG. 9 is a schematic view showing the motion of the locking member ofvthe rotary retractor between its locking and its release positions;

FIG. 10 is a plan view of a preferred mercury switch; and

FIG. 11 is a sectional view of the mercury switch of FIG. I0.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Now referring to the drawings,FIG. I illustrates a vehicle 10 having a conventional seat assembly 12in the vehicles passenger compartment. A safety seatbelt system,generally indicated at 14, is mounted adjacent the seat assembly 12 andincludes a lap belt 16 connected to a floor mounted retractor 18, and ashoulder belt 20 connected to an overhead mounted linear retractor 22.The lap belt 16 and shoulder belt 20 form part of a restraining systemfor an occupant 25 of the seat assembly 12. The seatbelt system 14allows the occupant 25 to perform various body motions within thepassenger compartment of the vehicle at such times as the vehicle is inan operating condition, but in response to various abnormal vehicleconditions, the system 14 restrains the occupant 25 from suddenly beingdisplaced from his seated position.

The mechanical components of the preferred retractor 22 are illustratedin FIGS. 1-5, and a preferred electrical circuitry for locking andunlocking the retractor is illustrated in FIG. 6. The retractor 22includes an elongated metal housing 24 which is fixedly attached to anoverhead portion of the vehicle 10, however it could be mounted in otherpositions within the vehicle such as in the back supporting portion ofthe seat assembly 12. The housing 24 is formed of a metal stamping witha generally channel-shaped cross section which includes a base 26 and apair of upturned sides 28 and 30.

Fastener means 32 attach the base of the housing to the vehicle'sceiling.

As best illustrated in FIGS. 2 and 2A, one end of the housing has anopening 34 for receiving the shoulder belt 20 toward a retractedposition within the housing. The housing 24 also has an integrallyformed anchor section 38 adjacent the opening 34. The inner end of theshoulder belt 20 is looped about the anchor member 38 and then stitchedto itself to form a permanent connection. A bar 40, adjacent opening 34,provides means for guiding the belt as it is moved into and out of thehousing.

A generally channel-shaped carriage 42 is slidably mounted between thesides 28 and 30 of the housing along a longitudinal path extendingbetween opposite ends of the housing. An elongated retracting spring 44has one end connected to the carriage 42 and its other end connected toa tab 46 that is adjacent the opening 34. A pulley 48 is rotatablymounted by a pin 50 to the housing so as to guide the spring between theend of the housing and its connection to the carriage 42. The bias ofthe spring urges the carriage 42 toward a fully retracted position inwhich it is adjacent the pulley 48.

A retractor bar 52 is carried at one end of the carriage 42. Theshoulder belt 20 is looped around the retractor bar in such a mannerthat as the carriage 42 is moved toward the pulley 48 by the spring 44,the belt is retracted into the housing, and as the belt 20 is extendedfrom the housing through the opening 34, it moves the carriage towardthe opening 34 against the bias of the spring 44. In its fully retractedposition, the belt is disposed in a pair of overlying linear foldswithin the housing. As the belt is extended through the opening 34, thecarriage moves toward the opening to unfold the belt to accommodate beltextension.

The sides 28 and 30 of the housing have elongated slots 54 and 56,respectively, which extend substantially the major length of thehousing. The ends of the retractor bar 52 extend through the slots 54and 56 to guide the carriage along the housing.

. A U-shaped member 58 is pivotally mounted at the other end of thecarriage by a pair of pins 60 and 62 so that its midsection can be movedeither toward or away from the base. A locking bar 64 is supportedbetween the legs of the member 58 with its ends extending into the slots54 and 56. The bar 64 is operable to function as a stop member toprevent belt extension. A spring 66 is mounted on the pin 62 and has oneleg connected to the retractor bar 52 and its other leg connected to thelocking bar 64 to bias the locking bar toward the base 26 and a lockingposition.

Each of the two slots 54 and 56 has a series of abutrnents 68 formedadjacent the base 26 which extend parallel to the path of motion of thecarriage 42 between its fully retracted and fully extended positions.When the carriage 42 is in an intermediate position associated with apartially retracted position of the belt 20, the opposite ends of thelocking bar 64 are engageable with the abutrnents 68 to lock thecarriage against further motion toward its fully extended position. Thespring 66 is operable to snap the locking bar into its locking positionto engage it with the abutrnents.

Referring to FIGS. 3. 4 and an electrical solenoid 70, carried on thecarriage 42, has a plunger 72 which is extended at such times as thesolenoid is electrically energized, and retracted when the solenoid isdeenergized. The plunger 72 has a cammed surface 74 engaged with thelocking bar 64 in such a manner that when the plunger is extended, itbiases the locking bar 64 toward its release position in which it isseparated from the abutrnents 68. When the plunger is retracted, itallows the locking bar 64 to be moved from its release position towardits locking position by the spring 66.

Three plastic pads 76 (only two shown) mounted on the base of thecarriage slidably support the carriage on the base 26 of the housing. Aplastic tubular housing 78 also mounted on the base of the carriage 42,supports a copper connector 80 that extends beyond one end of thehousing 78, and a copper brush 82 that is mounted adjacent the oppositeend of housing Thus it is to be understood that l have described themechanical components of a novel linear seatbelt retractor having acarriage 42 movably disposed in the housing 24 between fully retractedand fully extended positions, and connected to the belt 20 to retract ittoward the housing, or to allow t to be extended from the housing. Thesolenoid 70, when energized, retains the locking bar 64 in its releaseposition so that the belt can be freely extended by the user. However,at such times as the solenoid is deenergized, the spring 66 biases thelocking bar toward engagement with the abutrnents 68 to lock theretractor to prevent further belt extension.

Now referring to FIG. 6, the preferred circuitry 86 for energizing anddeenergizing the solenoid 70 is illustrated. The circuitry 86 isconnected in a conventional manner to the vehicle's ignition circuit 90which is energized by the ignition switch 92 when the vehicle's operatorintends to operate the vehicle. The circuitry 86 also includes a switch94 that is connected to the vehicle's hydraulic braking system 96 insuch a manner as to be opened to deenergize the solenoid 70 whenever thepressure in the circuit is increased to a predetermined level by theoperator suddenly braking the vehicle in order to bring it to a suddenstop. A conventional time-delay switch 98 is also connected between thebattery 88 and the solenoid 70 so that whenever the solenoid isdeenergized, a predetermined time interval must pass before the solenoidcan be reenergized. This is to avoid the possibility of a transientnormal condition causing the retractor to be unlocked.

A mercury switch 100 is also connected between the battery 88 and thesolenoid 70. The switch 100 is normally closed whenever the ignitionswitch is closed, but opens in response to the vehicle experiencing asudden change in velocity, or assuming an abnormal orientation. Such anorientation can be produced by the vehicle being laterally tipped on itsside, or being inclined at a fairly substantial angle as it climbs agrade. The mercury switch 100 is illustrated in detail in FIGS. 10 and l1.

In operation, the circuitry 86 connecting the solenoid to the battery 88is normally open whenever the vehicle is not being operated to avoidrunning down the battery 88. The switches 94 and 100 are normallyclosed. Switch 98 is opened whenever the circuit is deenergized. Whenthe ignition switch 92 is open, the solenoid is deenergized. When theoperator closes the ignition switch 92 in order to operate the vehicle,the time delay switch 98 is automatically closed after a predeterminedinterval to energize the solenoid 70 and move the locking bar 64 to itsrelease position. This allows the belt 20 to be freely extended by theoccupant 24. The belt remains free for extension to allow the occupantto move forwardly in the seat assembly 12. As he moves rearwardly, thespring 44 takes up any slack in the belt by moving the carriage 42toward its fully retracted position.

In the event of an emergency, as reflected in either the braking systemor in the mercury switch, the solenoid is automatically deenergized toretract the plunger 72 and allow the spring 66 to snap the locking barinto a pair of the abutrnents 68 to lock the carriage and the shoulderbelt against further extension. The belt 20 is then operative tocooperate with the other belt components to provide a restraint on theoccupant 24. If the vehicle resumes its nonnal operative condition, thesolenoid is automatically reenergized to unlock the retractor until asubsequent abnormal condition occurs or the ignition circuit isdeenergized.

Referring to FIGS. 10 and 11, the preferred mercury switch comprises aclosed, plastic housing 102 which is fixedly mounted on the vehicle. Thebase 104 of the housing has a dish-shaped configuration. A quantity ofmercury 106 in the housing normally assumes a position of equilibrium inthe center of the base 104. However if the vehicle is tilted or inclinedat an angle, the housing 102 also assumes the same angle, therebycausing the mercury 106 to be moved toward a position such as at A andin which it is spaced from the center of the housing. The mercury 106 isalso moved toward the edge of the base 104 if the vehicle experiences asudden change in momentum.

A pair of posts 108 and 110 are mounted adjacent the center of the base104. The posts 108 and 110 are spaced from one another and are formed ofan electrically conductive material to form a pair of switch elements.The post 108 is connected to a suitable lead 1 l2 and the post 110 isconnected to a lead 114. The two leads are connected to a coupling 116for electrically connecting the mercury switch 100 to the circuit 86 ofthe solenoid.

The post 108 has an upper end 118 which is bent in a circularconfiguration to substantially encircle the post 110. Thus the mercury106, in its position of equilibrium, contacts both of the posts 108 and110 to make an electrical connection in the circuit. However whendisplaced from the center of the base 104 as toward the position A"-inresponse to either an abnormal change in vehicle momentum or an abnormalvehicle orientation, in which the mercury becomes separated from eitherone or both of the posts, the electrical connection in the circuitry 86is broken to deenergize the solenoid. If the vehicle resumes its normalorientation, or a normal vehicle motion, the mercury 106 returns towardits center position to make an electrical connection between the twoposts.

FIGS. 7 to 10 illustrate another form of retractor 200 having a lockingmember that is connected to the circuitry 86 to automatically lock orunlock the retractor in response to predetermined vehicle conditions.The retractor 200 comprises a metal support 202 adapted to be mountedadjacent the floor of the vehicle. The support has a pair of spacedwalls 204 and 206 rotatably joumaling a windup shaft 208 which spans thetwo walls. A spiral windup spring 210 has one end connected to a slot212 of the shaft 208, and its other end connected to a slot 214 of ahousing 216 that is carried on the wall 204. The spring 210 biases theshaft 208 in the windup direction to retract a belt connected to theshaft, but allows it to be rotated in the opposite, unwind direction toaccommodate belt exten- SlOn.

A pair of circular ratchets 218 and 220 are fixedly carried on the shaft208 and support a reel 222. A belt 224 is mounted on the reel 222 withits inner end passed through a slot 226 of the reel, wrapped around theshaft 208 and then sewn to itself to form a permanent loop andconnection to the shaft. As the reel 222 is rotated with the shaft 208in the winding direction, the belt is retracted and wound into a rollabout the reel. The spring 210 functions to take up any slack in thebelt 224 by urging the shaft toward its windup direction.

A conventional tongue 228 carried on the outer end of the belt 224 isengageable with a conventional seatbelt buckle (not shown) to form acontinuous restraining element about the user in the conventionalmanner.

An elongated metal locking pawl 230 is pivotally supported between thewalls 218 and 220, and has a pair of teeth 232 and 234 that areengageable with the teeth of the ratchets 218 and 220 to lock the reelagainst rotation in the unwind direction. A lever 236, carried on theouter end of the pawl 230, has a tab 238 which extends normal to theaxis of the pawl's rotation. A solenoid 240, suited for electricalconnection to the circuitry 86, is mounted on the wall 206 in such amanner that when electrically energized, a solenoid plunger 242 which isin abutment with the tab 238 is extended to rotate the locking pawl 230toward its release position. In the pawl's release position. the teeth232 and 234 are separated from the ratchets 218 and 200 and allow thereel 222 to be freely rotated in either its wind or unwind directions.When the solenoid 240 is electrically deenergized, the plunger 242 isretracted to allow a spring 244, mounted on the outer end of the lockingpawl 230 to snap the pawl 230 toward its locking position in which theteeth 232 and 234 of the pawl engage ratchets 218 and 220, respectively,to prevent further belt extension.

Thus it is to be understood that l have described in detail twoembodiments of a novel seatbelt system in which the belt retractor isautomatically, electrically unlocked at such times as the vehiclesignition circuit is energized, automatically locked in response tovarious abnormal vehicle conditions to prevent belt extension as long asthe condition exists, and then automatically unlocked a predeterminedtime interval after the abnormal condition has passed.

Having described my invention, 1 claim:

1. in a vehicle having an ignition circuit connected to a source ofelectrical power, a seatbelt system, comprising:

a. a support;

b. a retractor member movable on the support in either a belt-extendingdirection, or a belt-retracting direction;

c. bias means for urging the retractor member in the beltretractingdirection;

d. a safety seatbelt connected to the retractor member so as to beretracted as the retractor member is moved in its belt-retractingdirection, and to be extended as the retractor member is moved in itsbelt-extending direction;

e. a stop member mounted on the support for motion between a stopposition in which it is operable to prevent belt extension, and arelease position in which it is inoperable to prevent belt extension;

f. a bias member operable to urge the stop member toward its stopposition;

g. an actuator connected to the stop member, and operable upon beingelectrically energized to move the stop member toward its releaseposition, the actuator being inoperable when deenergized to'prcventmovement of the stop member; and

h. circuitry means connected to the source of electrical power and tothe actuator for energizing the actuator to allow belt extension, andfor automatically deenergizing the actuator in response to apredetermined change in vehicle motion to prevent belt extension.

2. The seatbelt system as defined in claim 1, in which the circuitrymeans is operable to automatically deenergize the actuator in responseto deenergization of the ignition circuit.

3. The seatbelt system as defined in claim 1, in which the retractormember is rotatably mounted on the support for motion in oppositebelt-extending and belt-retracting directions.

4. In a vehicle having an ignition circuit, and a safety seatbelt systemincluding a retractor member movable in either a belt-retractingdirection, or a belt-extending direction, a first bias member operableto urge the retractor member movable in either a belt-retractingdirection, or a belt-extending direction, a first bias member operableto urge the retractor member in its belt-retracting direction, and astop member movable between a stop position in which it is operable toprevent motion of the retractor member in its belt-extending direction,and a release position in which it is inoperable to prevent motion ofthe retractor member, the combination comprising: a solenoid, connectedto the stop member; a circuitry means connected to said solenoid and toa source of electrical power, so that said solenoid is energized whensaid ignition circuit is energized, said circuitry means including acontainer, fixed with respect to the vehicle, a quantity of mercurydisposed in the container so as to be moved from a position ofequilibrium toward a second position in response to a predeterminedstate of vehicular motion, and a pair of spaced contacts connected inthe electrical circuit in series with the solenoid and the source ofelectrical power and disposed so as to be in contact with the mercury inits second position to energize the solenoid whereby the solenoid movesthe stop member towards its release position; and a bias member operableto automatically move the stop member toward its stop position when themercury is separated from its position of equilibrium to deenergize thesolenoid.

5. In a vehicle having an ignition circuit connected to a source ofelectrical power, a seatbelt system, comprising:

a. a support; b. a retractor member movable on the support in either a vbelt-extending direction, or a belt-retracting direction;

c. bias means for urging the retractor member in the beltretractingdirection;

d. a safety seatbelt connected to the retractor member so as to beretracted as the retractor member is moved in its belt-retractingdirection, and to be extended as the retractor member is moved in itsbelt-extending direction;

e. a stop member mounted on the support for motion between a stopposition in which it is operable to prevent belt extension, and arelease position in which it is inoperable to prevent belt extension;

f. a bias member operable to urge the stop member toward its stopposition;

g. an actuator connected to the stop member, and operable upon beingelectrically energized to move the stop member toward its releaseposition, the actuator being inoperable when deenergized to preventmovement of the stop member; and

h. circuitry means, operable to respond to a predetermined vehicleorientation for deenergizing the actuator, connected to the source ofelectrical power and to the actuator for energizing the actuator inresponse to a first predetennined condition of the vehicle to allow beltextension, and for automatically deenergizing the actuator in responseto a second predetennined condition of the vehicle to prevent beltextension.

6. In a vehicle having an ignition circuit connected to a source ofelectrical power, a seatbelt system, comprising:

a. support;

b. a retractor member movable on the support in either a belt-extendingdirection, or a belt-retracting direction;

c. bias means for urging the retractor member in the beltretractingdirection;

d. a safety seatbelt connected to the retractor member so as to beretracted as the retractor member is moved in its belt-retractingdirection, and to be extended as the retractor member is moved in itsbelt-extending direction;

e. a stop member mounted on the support for motion between a stopposition in which it is operable to prevent belt extension, and arelease position in which it is inoperable to prevent belt extension;

f. a bias member operable to urge the stop member toward its stopposition;

g. an actuator connected to the stop member, and operable upon beingelectrically energized to move the stop member toward its releaseposition, the actuator being inoperable when deenergized to preventmovement of the stop member;

h. a hydraulic braking circuit; and

. circuitry means, operable to deenergize the actuator in response topredetennined hydraulic pressures in said braking circuit, connected tothe source of electrical power and to the actuator for energizing theactuator in response to a first predetermined condition of the vehicleto allow belt extension, and for automatically deenergizing the actuatorin response to a second predetermined condition of the vehicle toprevent belt extension.

7. In a vehicle having an ignition circuit connected to a source ofelectrical power, a seatbelt system, comprising;

a. a support;

b. a retractor member movable on the support in either a belt-extendingdirection, or a belt-retracting direction;

c. bias means for urging the retractor member in the beltretractingdirection;

d. a safety seatbelt connected to the retractor member so as to beretracted as the retractor member is moved in its belt-retractingdirection, and to be extended as the retractor member is moved in itsbelt-extendin direction;

e. a stop member mounted on the support or motion between a stopposition in which it is operable to prevent belt extension, and arelease position in which it is inoperable to prevent belt extension;

f. a bias member operable to urge the stop member toward its stopposition;

g. an actuator connected to the stop member, and operable upon beingelectrically energized to move the stop member toward its releaseposition, the actuator being inoperable when deenergized to preventmovement of the stop member;

h. circuitry means connected to the source of electrical power and tothe actuator for energizing the actuator in response to a firstpredetermined condition of the vehicle to allow belt extension, and forautomatically deenergizing the actuator in response to a secondpredetennined condition of the vehicle to prevent belt extension; and

i. a time delay means, connected in said circuitry means, for delayingthe energization of said actuator for at least a predetermined timeinterval after it has been deenergized.

2% UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,610,361 Dated October S, 1971' Inventor(s) WILLIAM L- PRINGLE It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

IN THE SPECIFICATION Column 4, line 14, delete "t" and insert therefor iIN THE CLAIMS lines 4 to 7, delete "movable in either a beltretractingdirection, or a belt-extending direction, a first bias member operableto urge the retractor member" which has been repeated.

Signed and sealed this 6th day of June 1972.

Claim 4,

(SEAL) Attest:

EDWARD M.FLETCHER, JR. Attesting Officer ROBERT GOTISCHALK Commissionerof Patents

1. In a vehicle having an ignition circuit connected to a source ofelectrical power, a seatbelt system, comprising: a. a support; b. aretractor member movable on the support in either a beltextendingdirection, or a belt-retracting direction; c. bias means for urging theretractor member in the beltretracting direction; d. a safety seatbeltconnected to the retractor member so as to be retracted as the retractormember is moved in its beltretracting direction, and to be extended asthe retractor member is moved in its belt-extending direction; e. a stopmember mounted on the support for motion between a stop position inwhich it is operable to prevent belt extension, and a release positionin which it is inoperable to prevent belt extension; f. a bias memberoperable to urge the stop member toward its stop position; g. anactuator connected to the stop member, and operable upon beingelectrically energized to move the stop member toward its releaseposition, the actuator being inoperable when deenergized to preventmovement of the stop member; and h. circuitry means connected to thesource of electrical power and to the actuator for energizing theactuator to allow belt extension, and for automatically deenergizing theactuator in response to a predetermined change in vehicle motion toprevent belt extension.
 2. The seatbelt system as defined in claim 1, inwhich the circuitry means is operabLe to automatically deenergize theactuator in response to deenergization of the ignition circuit.
 3. Theseatbelt system as defined in claim 1, in which the retractor member isrotatably mounted on the support for motion in opposite belt-extendingand belt-retracting directions.
 4. In a vehicle having an ignitioncircuit, and a safety seatbelt system including a retractor membermovable in either a belt-retracting direction, or a belt-extendingdirection, a first bias member operable to urge the retractor membermovable in either a belt-retracting direction, or a belt-extendingdirection, a first bias member operable to urge the retractor member inits belt-retracting direction, and a stop member movable between a stopposition in which it is operable to prevent motion of the retractormember in its belt-extending direction, and a release position in whichit is inoperable to prevent motion of the retractor member, thecombination comprising: a solenoid, connected to the stop member; acircuitry means connected to said solenoid and to a source of electricalpower, so that said solenoid is energized when said ignition circuit isenergized, said circuitry means including a container, fixed withrespect to the vehicle, a quantity of mercury disposed in the containerso as to be moved from a position of equilibrium toward a secondposition in response to a predetermined state of vehicular motion, and apair of spaced contacts connected in the electrical circuit in serieswith the solenoid and the source of electrical power and disposed so asto be in contact with the mercury in its second position to energize thesolenoid whereby the solenoid moves the stop member towards its releaseposition; and a bias member operable to automatically move the stopmember toward its stop position when the mercury is separated from itsposition of equilibrium to deenergize the solenoid.
 5. In a vehiclehaving an ignition circuit connected to a source of electrical power, aseatbelt system, comprising: a. a support; b. a retractor member movableon the support in either a belt-extending direction, or abelt-retracting direction; c. bias means for urging the retractor memberin the belt-retracting direction; d. a safety seatbelt connected to theretractor member so as to be retracted as the retractor member is movedin its belt-retracting direction, and to be extended as the retractormember is moved in its belt-extending direction; e. a stop membermounted on the support for motion between a stop position in which it isoperable to prevent belt extension, and a release position in which itis inoperable to prevent belt extension; f. a bias member operable tourge the stop member toward its stop position; g. an actuator connectedto the stop member, and operable upon being electrically energized tomove the stop member toward its release position, the actuator beinginoperable when deenergized to prevent movement of the stop member; andh. circuitry means, operable to respond to a predetermined vehicleorientation for deenergizing the actuator, connected to the source ofelectrical power and to the actuator for energizing the actuator inresponse to a first predetermined condition of the vehicle to allow beltextension, and for automatically deenergizing the actuator in responseto a second predetermined condition of the vehicle to prevent beltextension.
 6. In a vehicle having an ignition circuit connected to asource of electrical power, a seatbelt system, comprising: a. support;b. a retractor member movable on the support in either a belt-extendingdirection, or a belt-retracting direction; c. bias means for urging theretractor member in the belt-retracting direction; d. a safety seatbeltconnected to the retractor member so as to be retracted as the retractormember is moved in its belt-retracting direction, and to be extended asthe retractor member is moved in its belt-extending direction; e. a stopmembeR mounted on the support for motion between a stop position inwhich it is operable to prevent belt extension, and a release positionin which it is inoperable to prevent belt extension; f. a bias memberoperable to urge the stop member toward its stop position; g. anactuator connected to the stop member, and operable upon beingelectrically energized to move the stop member toward its releaseposition, the actuator being inoperable when deenergized to preventmovement of the stop member; h. a hydraulic braking circuit; and i.circuitry means, operable to deenergize the actuator in response topredetermined hydraulic pressures in said braking circuit, connected tothe source of electrical power and to the actuator for energizing theactuator in response to a first predetermined condition of the vehicleto allow belt extension, and for automatically deenergizing the actuatorin response to a second predetermined condition of the vehicle toprevent belt extension.
 7. In a vehicle having an ignition circuitconnected to a source of electrical power, a seatbelt system,comprising: a. a support; b. a retractor member movable on the supportin either a belt-extending direction, or a belt-retracting direction; c.bias means for urging the retractor member in the belt-retractingdirection; d. a safety seatbelt connected to the retractor member so asto be retracted as the retractor member is moved in its belt-retractingdirection, and to be extended as the retractor member is moved in itsbelt-extending direction; e. a stop member mounted on the support formotion between a stop position in which it is operable to prevent beltextension, and a release position in which it is inoperable to preventbelt extension; f. a bias member operable to urge the stop member towardits stop position; g. an actuator connected to the stop member, andoperable upon being electrically energized to move the stop membertoward its release position, the actuator being inoperable whendeenergized to prevent movement of the stop member; h. circuitry meansconnected to the source of electrical power and to the actuator forenergizing the actuator in response to a first predetermined conditionof the vehicle to allow belt extension, and for automaticallydeenergizing the actuator in response to a second predeterminedcondition of the vehicle to prevent belt extension; and i. a time delaymeans, connected in said circuitry means, for delaying the energizationof said actuator for at least a predetermined time interval after it hasbeen deenergized.